This is very easy to find with a simple google search. Here's the year-to-date spending for 2023:
$1.01T social security
$673B health
$636B medicare
$623B income security
$610B defense
$494B net interest
$220B veteran benefits & services
$201B education, training, employment, and social services
$89B transportation
$74B community and regional development
$179B other
From what I know there are a number of legal complications/liabilities to hosting NSFW content. For most people hosting instances it's just not worth the hassle given that users can still interact with the NSFW communities on the dedicated instance.